Multiple Application Propfan Study (MAPS): Advanced tactical transport

This study was conducted to ascertain potential benefits of a propfan propulsion system application to a blended wing/body military tactical transport. Based on a design cruise Mach no. of 0.75 for the design mission, the results indicate a significant advantage in various figures of merit for the propfan over those of a comparable technology turbofan. Although the propfan has a 1.6 percent greater takeoff gross weight, its life cycle cost is 5.3 percent smaller, partly because of a 27 percent smaller specific fuel consumption. When employed on alternate missions, the propfan configuration offers significantly improved flexibility and capability: an increase in sea level penetration distance of more than 100 percent, or in time-on-station of 24 percent, or in deployment payload of 38 percent

Concise Synthesis of (+)- allo

3-Methyl vinyl aziridine undergoes a mild MgI2-promoted S(N)2' ring opening and concomitant cyclization with fumarate Michael acceptors to give trisubstituted pyrrolidines. The process is efficient and highly diastereoselective. This methodology has been applied to a concise asymmetric synthesis of (+)-allo-kainic acid.</p

Cyclic 1,2-Dinitrogen Compounds through N,N'-Di(Methoxycarbonyl)Hydrazinium Intermediates

Contains fulltext : 26292.PDF (publisher's version ) (Open Access

Influence of patients’ preoperative expectations on postoperative outcomes after total knee or hip arthroplasty: a systematic review

Purpose: The association between preoperative expectations and treatment outcomes in total hip arthroplasty (THA) or total knee arthroplasty (TKA) is still unclear. Therefore the aim is to examine the association between preoperative outcome expectations, process expectations, and self-efficacy, and the postoperative outcomes overall outcome, pain, function, stiffness, satisfaction, and quality of life following THA/TKA. Methods: A systematic review with narrative synthesis was conducted. PubMed, EMBASE, PsycINFO, CINAHL and Cochrane Library were searched from inception to October 17, 2022. Included were prospective longitudinal cohort studies published in English, German, or Dutch, with an adult population undergoing THA/TKA, and including at least one measure of preoperative expectations and the postoperative outcomes mentioned earlier. Two independent reviewers screened the retrieved articles for eligibility, a third solved disagreements. Risk of bias (RoB) was assessed using the QUIPS tool. Results: Of the 50 included studies, 38 had high RoB and 12 moderate RoB. Unadjusted results suggest a positive association between preoperative outcome expectations and overall outcome in the medium and long term, and between self-efficacy and change in ‘overall outcome’ in the long term. Adjusted results suggest positive associations between outcome expectations and function and between self-efficacy and overall outcome in the medium term, and for outcome expectations with pain and change in pain, respectively, and self-efficacy and stiffness in the long term. Conclusions: Preoperative expectations show a possible positive association with specific outcome measures, such as pain or function. For future research, it is advised to link matching specific expectations with specific outcomes

Combining a reduced field of excitation with SENSE-based parallel imaging for maximum imaging efficiency

PURPOSE: To show that a combination of parallel imaging using sensitivity encoding (SENSE) and inner volume imaging (IVI) combines the known benefits of both techniques. SENSE with a reduced field of excitation (rFOX) is termed rSENSE. THEORY AND METHODS: The noise level in SENSE reconstructions is reduced by removing voxels from the unfolding process that are rendered silent by using rFOX. The silent voxels need to be identified beforehand, this is done by using rFOX in the coil sensitivity maps. In vivo experiments were performed at 7 Tesla using a 32-channel receive coil. RESULTS: Good image quality could be obtained in vivo with rSENSE at acceleration factors that are higher than could be obtained using SENSE or IVI alone. With rSENSE we were also able to accelerate scans using an rFOX that was purposely designed to be imperfect or incompatible at all with IVI. CONCLUSION: rSENSE has been demonstrated in vivo with two-dimensionally selective radiofrequency pulses. Besides allowing additional scan acceleration, it offers a greater robustness and flexibility than IVI. The proposed method can be used with other field strengths, anatomies and other rFOX techniques. Magn Reson Med 78:88-96, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution Non Commercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes

Influence of health system and patient characteristics on expectations and outcome in total hip arthroplasty patients in the Dutch-German border region: protocol for a mixed-methods prospective observational comparative study (hip across)

INTRODUCTION: Total hip arthroplasty (THA) is the treatment of choice for end-stage osteoarthritis of the hip. Management of THA differs between countries, and it is hypothesised that this can influence patients' expectations and self-efficacy. Using Chen's intervening mechanism evaluation approach, this study aims to explore how structure of care influences expectations and self-efficacy of patients undergoing THA, and how expectations and self-efficacy in turn influence outcome in terms of perceived physical function and satisfaction. METHODS AND ANALYSIS: A mixed-methods study will be conducted in two German and two Dutch hospitals near the Dutch-German border. In the quantitative part, patients will complete questionnaires at three timepoints: preoperatively and at 3 and 6 months postoperatively. Data analysis will include multiple regression analysis and structural equation modelling. In the qualitative part, interviews will be held with patients (preoperatively and 3 months postoperatively) and healthcare providers. Analysis will be performed using structured qualitative content analysis. ETHICS AND DISSEMINATION: The study is approved by the Institutional Review Boards of both Carl von Ossietzky University Oldenburg (2021-167) and University Medical Center Groningen (METc 2021/562 and METc 2021/601). The results will be disseminated in the international scientific community via publications and conference presentations. TRIAL REGISTRATION NUMBER: The study is registered in the German Clinical Trials Registry (DRKS: DRKS00026744)

Low fecal calprotectin predicts sustained clinical remission in inflammatory bowel disease patients : a plea for deep remission

BACKGROUND AND AIMS: Mucosal healing has become the treatment goal in patients with ulcerative colitis (UC) and Crohn's disease (CD). Whether low fecal calprotectin levels and histological healing combined with mucosal healing is associated with a further reduced risk of relapses is unknown. METHODS: Patients with CD, UC or inflammatory bowel disease-unclassified (IBD-U) scheduled for surveillance colonoscopy collected a stool sample prior to bowel cleansing. Only patients with mucosal healing (MAYO endoscopic score of 0) were included. Fecal calprotectin was measured using a quantitative enzyme-linked immunosorbent assay (R-Biopharm, Germany). Biopsies were obtained from four colonic segments, and histological disease severity was assessed using the Geboes scoring system. Patients were followed until the last outpatient clinic visit or the development of a relapse, which was defined as IBD-related hospitalization, surgery or step-up in IBD medication. RESULTS: Of the 164 patients undergoing surveillance colonoscopy, 92 patients were excluded due to active inflammation or missing biopsies. Of the remaining 72 patients (20 CD, 52 UC or IBD-U), six patients (8%) relapsed after a median follow-up of 11 months (range 5-15 months). Median fecal calprotectin levels at baseline were significantly higher for patients who relapsed compared with patients who maintained remission (284 mg/kg vs. 37 mg/kg. p < 0.01). Fecal calprotectin below 56 mg/kg was found to optimally predict absence of relapse during follow-up with 64% sensitivity, 100% specificity, 100% negative predictive value and 20% positive predictive value. The presence or absence of active inflammation determined by Geboes cut-off score of 3.1 was less strongly associated with the risk of relapse (64% sensitivity, 33% specificity, 9% negative predictive value and 92% positive predictive value. CONCLUSION: Low calprotectin levels identify IBD patients who remain in stable remission during follow-up